#799982 by tstoeckler, StuartJNCC: Fixed Updating D6 -> D7 fails if the D6 site has Date module applied.

#680992 by Berdir, catch, andypost, douggreen, mr.baileys: Fixed comments are added to search index without checking access.

#668640 by casey, aspilicious, et al: Re-implement Overlay without jQuery UI Dialog; massive performance improvement, helps address several critical issues.

#794184 by JacobSingh, catch, chx: Fixed contact_update_7002() fails when the contact module is not enabled.

#797024 follow-up by justinrandell: Remove critical performance regression due to stale file time values.

#797024 by pwolanin, justinrandell: Fixed Moving a class between files can cause SQL errors on registry rebuild.

- Patch #803212 by effulgentsia, Heine: protection against forgery of input selection value doesn't work with checkboxes.

- Patch #807396 by Berdir, carlos8f, David_Rothstein: database errors not displaying during install.

- Patch #312144 by CorniI, dropcube, EvanDonovan, Damien Tournoud, David_Rothstein, tstoeckler: install fails when default.settings.php is not present.

- Patch #545610 by brandonojc, Everett Zufelt, mgifford: search form needs a header for accessibility.

- Patch #701358 by aaron, quicksketch, chx, pwolanin, aspilicious: the file API presumes a hiearchical file storage.